Journal articles: 'Oscillating movement'

1

He, Zhang-Ming, Deng-Long Wang, Yan-Chao She, Jian-Wen Ding, and Xiao-Hong Yan. "Nonperiodic Oscillation of Bright Solitons in Condensates with a Periodically Oscillating Harmonic Potential 10.5560/ZNA.2012-0085." Zeitschrift für Naturforschung A 67, no. 12 (December 1, 2012): 723–28. http://dx.doi.org/10.5560/zna.2012-0085.

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Considering a periodically oscillating harmonic potential, we explored the dynamic properties of bright solitons in a Bose-Einstein condensate by using Darboux transformation. It is found that the soliton movement exhibits a nonperiodic oscillation under a slow oscillating potential, while it is hardly affected under a fast oscillating potential. Furthermore, the head-on and/or ‘chase’ collisions of two solitons have been obtained, which could be controlled by the oscillation frequency of the potential.

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Gutnik, B. J., and B. Hyland. "Lateralized Spatial Strategies in Oscillating Drawing Movements." Perceptual and Motor Skills 84, no. 2 (April 1997): 435–51. http://dx.doi.org/10.2466/pms.1997.84.2.435.

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Kinematic characteristics and lateral differences between two upper extremities were investigated in a unimanual graphic task involving fast and precise oscillating movements on the vertical plane. The spatial locations of sequential reversal points were used to calculate the pairs of angles, relative to the horizontal axis. The point biserial coefficient of correlation was used to analyze the difference between big and large angles and their sequence in each pair. Three main groups (A, B, and C) of performance models were distinguished in 132 tests by 33 strongly right-handed male subjects. Group A showed strong variation in vertical movement, Group B covariation in vertical and horizontal vectors, while Group C reflected independent variation of both vertical and horizontal directions. It is suggested that the movement strategies might reflect three different models of motor control involving coupling of an oscillator controlling pools of motoneurons which regulate horizontal movements with an oscillator controlling vertical movement (Groups A + B) or with nonoscillating control signal (Group B). It is argued that Group A represents the simplest strategy and only performance Type A met by the left hand.

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Wan, Xiaohu, Daniela Cimini, Lisa A. Cameron, and E. D. Salmon. "The coupling between sister kinetochore directional instability and oscillations in centromere stretch in metaphase PtK1 cells." Molecular Biology of the Cell 23, no. 6 (March 15, 2012): 1035–46. http://dx.doi.org/10.1091/mbc.e11-09-0767.

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Kinetochores bound to kinetochore microtubules (kMTs) exhibit directional instability in mammalian and other mitotic vertebrate cells, oscillating between poleward (P) and away-from-the-pole (AP) movements. These oscillations are coupled to changes in length of kMTs in a way that maintains a net stretch of the centromere. To understand how sister kinetochore directional instability and kMT plus-end dynamic instability are coupled to oscillations in centromere stretch, we tracked at high resolution the positions of fluorescent kinetochores and their poles for oscillating chromosomes within spindles of metaphase PtK1 cells. We found that the kinetics of P and AP movement are nonlinear and different. By subtracting contributions from the poleward flux of kMTs, we found that maximum centromere stretch occurred when the leading kinetochore switched from depolymerization to polymerization, whereas minimum centromere stretch occurred on average 7 s after the initially trailing kinetochore switched from polymerization to depolymerization. These differences produce oscillations in centromere stretch at about twice the frequency of kinetochore directional instability and at about twice the frequency of centromere oscillations back and forth across the spindle equator.

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Kobayashi, H. "Annular Cascade Study of Low Back-Pressure Supersonic Fan Blade Flutter." Journal of Turbomachinery 112, no. 4 (October 1, 1990): 768–77. http://dx.doi.org/10.1115/1.2927720.

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Low back-pressure supersonic fan blade flutter in the torsional mode was examined using a controlled-oscillating annular cascade test facility. Precise data of unsteady aerodynamic forces generated by shock wave movement, due to blade oscillation, and the previously measured data of chordwise distributions of unsteady aerodynamic forces acting on an oscillating blade, were joined and, then, the nature of cascade flutter was evaluated. These unsteady aerodynamic forces were measured by direct and indirect pressure measuring methods. Our experiments covered a range of reduced frequencies based on a semichord from 0.0375 to 0.547, six interblade phase angles, and inlet flow velocities from subsonic to supersonic flow. The occurrence of unstalled cascade flutter in relation to reduced frequency, interblade phase angle, and inlet flow velocity was clarified, including the role of unsteady aerodynamic blade surface forces on flutter. Reduced frequency of the flutter boundary increased greatly when the blade suction surface flow became transonic flow. Interblade phase angles that caused flutter were in the range from 40 to 160 deg for flow fields ranging from high subsonic to supersonic. Shock wave movement due to blade oscillation generated markedly large unsteady aerodynamic forces which stimulated blade oscillation.

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5

Upnere, S. "Numerical Study of Flow-Induced Vibrations of Multiple Flexibly-Mounted Cylinders in Triangular Array." Latvian Journal of Physics and Technical Sciences 55, no. 5 (October 1, 2018): 43–53. http://dx.doi.org/10.2478/lpts-2018-0035.

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Abstract The paper presents the numerical study of vibrating multiple flexibly-mounted cylinders in a triangular rod bundle. Behavioural trends of six different clusters of oscillating rods have been analysed. The influence of neighbour cylinders on the central cylinder oscillation characteristics is analysed. Finite volume solver of open source computational fluid dynamics is used to calculate the fluid flow in the channel with the cylinder array. Built-in six degree-of-freedoms solver is utilised to simulate cylinder movement. Oscillating cylinders have two degrees-of-freedom. The obtained results are compared with numerical results available in the literature.

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Islam, Nabirul, Jochen Schanz, David Kolb, and Harald Riegel. "Improvement of Surface Quality and Process Area Rate in Selective Laser Melting by Beam Oscillation Scan Technique." Journal of Materials Engineering and Performance 30, no. 7 (May 5, 2021): 5108–17. http://dx.doi.org/10.1007/s11665-021-05665-9.

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AbstractSelective laser melting (SLM) has potential benefits for additive manufacturing of complex and precise metal parts with required mechanical and material properties. However, the improvement of surface quality and the minimization of fabrication time still remark a challenge for efficient manufacturing by SLM. Among the process parameters, the scan strategy has a significant influence on process stability and quality of the final manufactured three-dimensional products. This paper demonstrates the investigation of an alternative scan strategy to improve the surface quality with a reduction of fabrication time and laser energy input. Hereby, the scan strategy is performed by a conventional linear and oscillating laser beam movement in a self-developed SLM process chamber. Comparative analysis of the manufactured specimens regarding surface quality and density was performed. The investigations in oscillating laser beam movement show a decrease in the average variation of surface profile up to 50% relative to the experimented conventional linear scan technique. Due to an increased melt pool during the oscillation beam movement, the hatch distance was increased. As a result, the applied laser energy input was reduced by more than 28%, and the area rate was raised up to 50% compared to the conventional linear laser beam movement.

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7

Lu, Liang, Shirang Long, and Kangwu Zhu. "A Numerical Research on Vortex Street Flow Oscillation in the Double Flapper Nozzle Servo Valve." Processes 7, no. 10 (October 11, 2019): 721. http://dx.doi.org/10.3390/pr7100721.

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The oscillating flow field of the double nozzle flapper servo valve pre-stage is numerically analyzed through Large Eddy Simulation (LES) turbulent modeling with the previous grid independence verification. The vortex street flow phenomenon can be observed when the flow passes through the nozzle flapper channel, the vortex alternating in each side produces the periodical flow oscillation. The structural and flow parameter effects on the oscillating flow are emphasized, and it could be determined that the pressure on the flapper is nearly proportional to the flow velocity and inversely proportional to the actual distance between the flapper and the nozzle. On the other hand, the main frequency of oscillation decreases with the velocity and increases with the distance between the nozzle flapper. The main stage movement is further considered with a User Defined Function (UDF), and it could be determined that the influences of the structural and flow parameters on the flow oscillation are rarely changed, but the main frequencies drop, generally.

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8

Bulgakov, V., V. Adamchuk, І. Holovach, and Ye Ihnatiev. "Mathematical model of the movement of a towed machine for cleaning beet tops residues from root crop heads." Agricultural Science and Practice 4, no. 1 (April 15, 2017): 3–10. http://dx.doi.org/10.15407/agrisp4.01.003.

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The work of a tractor-towed machine for cleaning beet top residues from root crop heads, when used with supporting pneumatic wheels, is accompanied with its oscillations in the vertical plane, which has consider- able impact on the quality of implementing the technological process. Therefore, the determination of opti- mal parameters for the cleaning machine, ensuring more stable movement of its cleaning working tool, in the longitudinal-vertical plane fi rst and foremost, is an important task of the mechanization of sugar beet grow- ing industry. Aim. To enhance the effi ciency of cleaning sugar beet top residues from root crop heads via the elaboration of the mathematical model of the oscillating movement of the towed machine for cleaning beet top residues from root crop heads in the longitudinal-vertical plane. Methods. The methods of building computational mathematical models for the functioning of agricultural machines and equipment, based on theoretical mechanics and advanced mathematics, were used. Results. The elaborated equivalent scheme of the movement of the towed cleaning machine was used to obtain the system of two non-linear differential equations for detailed study of the oscillations of the root crop head cleaner in the longitudinal-vertical plane while its supporting pneumatic wheels are moving along uneven soil surface. The mathematical model for the movement of the cleaner with horizontal cleaning roller, elaborated on the basis of initial dynamics equa- tions in the Lagrangian form of the second kind, allowed determining the connection between constructive and kinematic parameters of the vehicle and its oscillating characteristics. The established dependencies formed the prerequisites for further mathematical digital modelling of the parameters of the towed machine for cleaning of root crop heads with a horizontal cleaning roller. Conclusions. The established computation- al model allows optimizing the values of several parameters, characterizing the oscillations of the machine in the longitudinal-vertical plane.

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Ohorodnyk, N., K. Smolianinov, and M. Ratsky. "Cellular and humoral immunity of carp at the action of biologically active additives." Agricultural Science and Practice 4, no. 1 (April 15, 2017): 70–73. http://dx.doi.org/10.15407/agrisp4.01.070.

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The work of a tractor-towed machine for cleaning beet top residues from root crop heads, when used with supporting pneumatic wheels, is accompanied with its oscillations in the vertical plane, which has consider- able impact on the quality of implementing the technological process. Therefore, the determination of opti- mal parameters for the cleaning machine, ensuring more stable movement of its cleaning working tool, in the longitudinal-vertical plane fi rst and foremost, is an important task of the mechanization of sugar beet grow- ing industry. Aim. To enhance the effi ciency of cleaning sugar beet top residues from root crop heads via the elaboration of the mathematical model of the oscillating movement of the towed machine for cleaning beet top residues from root crop heads in the longitudinal-vertical plane. Methods. The methods of building computational mathematical models for the functioning of agricultural machines and equipment, based on theoretical mechanics and advanced mathematics, were used. Results. The elaborated equivalent scheme of the movement of the towed cleaning machine was used to obtain the system of two non-linear differential equations for detailed study of the oscillations of the root crop head cleaner in the longitudinal-vertical plane while its supporting pneumatic wheels are moving along uneven soil surface. The mathematical model for the movement of the cleaner with horizontal cleaning roller, elaborated on the basis of initial dynamics equa- tions in the Lagrangian form of the second kind, allowed determining the connection between constructive and kinematic parameters of the vehicle and its oscillating characteristics. The established dependencies formed the prerequisites for further mathematical digital modelling of the parameters of the towed machine for cleaning of root crop heads with a horizontal cleaning roller. Conclusions. The established computation- al model allows optimizing the values of several parameters, characterizing the oscillations of the machine in the longitudinal-vertical plane.

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10

Gutnik, B. J., J. Nicholson, W. Go, D. Gale, and D. Nash. "Are Temporal Characteristics of Fast Repetitive Oscillating Movement Invariant?" Perceptual and Motor Skills 96, no. 3 (June 2003): 1027–39. http://dx.doi.org/10.2466/pms.2003.96.3.1027.

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11

Nago, H., and S. Maeno. "Movement of Sand behind Reventment under Oscillating Water Pressure." PROCEEDINGS OF THE JAPANESE CONFERENCE ON HYDRAULICS 32 (1988): 595–600. http://dx.doi.org/10.2208/prohe1975.32.595.

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12

Lu, Xingjie, Lin Ren, Qingyu Gao, Yuemin Zhao, Shaorong Wang, Jiaping Yang, and Irving R. Epstein. "Photophobic and phototropic movement of a self-oscillating gel." Chemical Communications 49, no. 70 (2013): 7690. http://dx.doi.org/10.1039/c3cc44480e.

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13

Wall, C., A. Assad, G. Aharon, P. S. Dimitri, and L. R. Harris. "The human oculomotor response to simultaneous visual and physical movements at two different frequencies." Journal of Vestibular Research 11, no. 2 (July 1, 2001): 81–89. http://dx.doi.org/10.3233/ves-2001-11203.

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In order to investigate interactions in the visual and vestibular systems' oculomotor response to linear movement, we developed a two-frequency stimulation technique. Thirteen subjects lay on their backs and were oscillated sinusoidally along their z-axes at between 0.31 and 0.81 Hz. During the oscillation subjects viewed a large, high-contrast, visual pattern oscillating in the same direction as the physical motion but at a different, non-harmonically related frequency. The evoked eye movements were measured by video-oculography and spectrally analysed. We found significant signal level at the sum and difference frequencies as well as at other frequencies not present in either stimulus. The emergence of new frequencies indicates non-linear processing consistent with an agreement-detector system that have previously proposed.

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THO, PAUL, RICHARD MANASSEH, and ANDREW OOI. "Cavitation microstreaming patterns in single and multiple bubble systems." Journal of Fluid Mechanics 576 (March 28, 2007): 191–233. http://dx.doi.org/10.1017/s0022112006004393.

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Cavitation microstreaming is a well-known phenomenon; however, few flow visualizations or measurements of the velocity fields have been conducted. In this paper micro-PIV (particle image velocimetry) measurements and streak photography were used to study the flow field around a single and two oscillating bubbles resting on a solid boundary. The mode of oscillation of the bubble was also measured in terms of the variation in the radius of the bubble and the movement of the bubble's centroid so that the streaming flow field could be accurately related to the bubble's oscillatory motion. The mode of oscillation was found to vary primarily with the applied acoustic frequency. Several modes of oscillation were investigated, including translating modes where the bubble's centroid moves along either a single axis, an elliptical orbit or a circular orbit. The flow field resulting from these oscillation modes contains closed streamlines representing vortical regions in the vicinity of the bubble. The translating modes were observed to occur in sequential order with the acoustic excitation frequency, changing from a translation along a single axis, to an elliptical orbit and finally to a circular orbit, or vice versa. Following this sequence, there is a corresponding transformation of the streaming pattern from a symmetrical flow structure containing four vortices to a circular vortex centred on the bubble. Despite some inconsistencies, there is general agreement between these streaming patterns and those found in existing theoretical models. Volume and shape mode oscillations of single bubbles as well as several different cases of multiple bubbles simultaneously oscillating with the same frequency and phase were also investigated and show a rich variety of streaming patterns.

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15

Ansini, Nadia, Andrea Braides, and Johannes Zimmer. "Minimizing movements for oscillating energies: the critical regime." Proceedings of the Royal Society of Edinburgh: Section A Mathematics 149, no. 03 (December 27, 2018): 719–37. http://dx.doi.org/10.1017/prm.2018.46.

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AbstractMinimizing movements are investigated for an energy which is the superposition of a convex functional and fast small oscillations. Thus a minimizing movement scheme involves a temporal parameter τ and a spatial parameter ε, with τ describing the time step and the frequency of the oscillations being proportional to 1/ε. The extreme cases of fast time scales τ ≪ ε and slow time scales ε ≪ τ have been investigated in [4]. In this paper, the intermediate (critical) case of finite ratio ε/τ > 0 is studied. It is shown that a pinning threshold exists, with initial data below the threshold being a fixed point of the dynamics. A characterization of the pinning threshold is given. For initial data above the pinning threshold, the equation and velocity describing the homogenized motion are determined.

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16

Popescu, Daniel. "DETERMINING THE BALANCE CONFIGURATION, IN CASE OF THE OSCILLATING MOVEMENT OF THE MAIN SPINDLE AT CNC LATHE." International Journal of Engineering Technologies and Management Research 7, no. 6 (June 12, 2020): 41–46. http://dx.doi.org/10.29121/ijetmr.v2020.i7.6.692.

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In the paper we present a mathematical model through which are determined the balance conditions, needed for the stability analysis of the oscillating movement of the main spindle at CNC lathe. We take into account Hamilton's variation principle, the axiom of impulse derivative and the axiom of kinetic moment derivative. We present the general movement equations that generate the oscillations based on the calculus hypotheses, performing the introduction of the external solicitations. Establishment of the balance configuration is done by imposing the conditions that the system of forces that act upon the ensemble spindle – bearings - tool causes a deformation of the spindle, without producing spindle vibration. We obtain the new differential equations of the movement, in which the forces and moments are determined from the static case, based on which we can determine the integration constants in the characteristic points of the main spindle.

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Popescu, Daniel. "DETERMINING THE BALANCE CONFIGURATION, IN CASE OF THE OSCILLATING MOVEMENT OF THE MAIN SPINDLE AT CNC LATHE." International Journal of Engineering Technologies and Management Research 7, no. 6 (June 12, 2020): 41–46. http://dx.doi.org/10.29121/ijetmr.v7.i6.2020.692.

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In the paper we present a mathematical model through which are determined the balance conditions, needed for the stability analysis of the oscillating movement of the main spindle at CNC lathe. We take into account Hamilton's variation principle, the axiom of impulse derivative and the axiom of kinetic moment derivative. We present the general movement equations that generate the oscillations based on the calculus hypotheses, performing the introduction of the external solicitations. Establishment of the balance configuration is done by imposing the conditions that the system of forces that act upon the ensemble spindle – bearings - tool causes a deformation of the spindle, without producing spindle vibration. We obtain the new differential equations of the movement, in which the forces and moments are determined from the static case, based on which we can determine the integration constants in the characteristic points of the main spindle.

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Cowin, Stephen C., Gaffar Gailani, and Mohammed Benalla. "Hierarchical poroelasticity: movement of interstitial fluid between porosity levels in bones." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 367, no. 1902 (September 13, 2009): 3401–44. http://dx.doi.org/10.1098/rsta.2009.0099.

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The governing equations for the theory of poroelastic materials with hierarchical pore space architecture and compressible constituents undergoing small deformations are developed. These equations are applied to the problem of determining the exchange of pore fluid between the vascular porosity (PV) and the lacunar–canalicular porosity (PLC) in bone tissue due to cyclic mechanical loading and blood pressure oscillations. The result is basic to the understanding of interstitial flow in bone tissue that, in turn, is basic to understanding of nutrient transport from the vasculature to the bone cells buried in the bone tissue and to the process of mechanotransduction by these cells. A formula for the volume of fluid that moves between the PLC and PV in a cyclic loading is obtained as a function of the cyclic mechanical loading and blood pressure oscillations. Formulas for the oscillating fluid pore pressure in both the PLC and the PV are obtained as functions of the two driving forces, the cyclic mechanical straining and the blood pressure, both with specified amplitude and frequency. The results of this study also suggest a PV permeability greater than 10 −9 m 2 and perhaps a little lower than 10 −8 m 2 . Previous estimates of this permeability have been as small as 10 −14 m 2 .

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Wortmann, M., and W. Zarnack. "WING MOVEMENTS AND LIFT REGULATION IN THE FLIGHT OF DESERT LOCUSTS." Journal of Experimental Biology 182, no. 1 (September 1, 1993): 57–69. http://dx.doi.org/10.1242/jeb.182.1.57.

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1. We simultaneously recorded lift/body weight, flight speed, body angle and 12 variables of wing movement for locusts performing tethered long-term flight with low movement scatter. The movements of the forewings and hindwings were recorded in three dimensions by means of miniature induction coils. 2. By adjusting the body angle, we could reproducibly manipulate lift generation as a consequence of induced changes in the wings' movement patterns. We were therefore able to analyse various relationships between the movement patterns and lift. 3. The most prominent variations of kinematic variables were observed for the forewing movements. The relative lift and the steady angle of pitch were positively correlated but there was a negative correlation between relative lift and pitching amplitude. We found no correlation between relative lift and flapping amplitude. Our results seem to correspond to a new theory about unsteady aerodynamics of oscillating aerofoils. 4. We sometimes observed variations in lagging. 5. The forewing downstroke was delayed by 0–8 ms following the hindwing downstroke. Relative lift was positively correlated to this delay.

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Shi, Qiang, and Chuan-Feng Chen. "Step-by-step reaction-powered mechanical motion triggered by a chemical fuel pulse." Chemical Science 10, no. 8 (2019): 2529–33. http://dx.doi.org/10.1039/c8sc05469j.

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21

Quadrio, Maurizio. "Drag reduction in turbulent boundary layers by in-plane wall motion." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 369, no. 1940 (April 13, 2011): 1428–42. http://dx.doi.org/10.1098/rsta.2010.0366.

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Drag-reduction techniques capable of reducing the level of turbulent friction through wall-parallel movement of the wall are described, with special emphasis placed on spanwise movement. The discussion is confined to active open-loop control strategies, although feedback control is briefly mentioned with regard to peculiarities of spanwise sensing and/or actuation. Theoretical considerations are first given to explain why spanwise motion is expected to be particularly effective in skin-friction drag reduction. A review of the spanwise oscillating-wall technique is given next, with discussion of recent results and prospects. Last, waves of spanwise velocity are addressed, either spanwise- or streamwise-travelling. The latter include the oscillating wall as a special case. The generalized Stokes layer—i.e. the laminar, transverse oscillating boundary layer that develops under the action of the streamwise-travelling waves—is described, and its importance in determining turbulent drag reduction discussed. Finally, open issues like energetic efficiency and its dependence on Reynolds number are addressed.

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22

Demokritov, Vladimir, and Aleksandr Oleshkevich. "DYNAMICS DESIGN OF MECHANISM OF CRANE TROLLEY MOVEMENT." TRANSPORT 21, no. 4 (December 31, 2006): 284–85. http://dx.doi.org/10.3846/16484142.2006.9638080.

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A crane trolley with a hanging oscillating load was considered. Normal and tangential acceleration of the load and difference between the weight of the load and the strain of the rope are taken into account. Three differential dynamic equations were made. After the solution of the system one nonlinear equation was got; the solution of it was found. Frequency of own vibrations, amplitude and phase were defined taking primary conditions into consideration. The condition of resonance prevention was revealed.

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Zhang, Zhi Li, De Cai Li, Li Ming Huang, Qi Han, and Dan Shi. "Experimental Study on Magnetic Fluids Viscous Damper." Key Engineering Materials 492 (September 2011): 268–72. http://dx.doi.org/10.4028/www.scientific.net/kem.492.268.

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Magnetic fluids viscous damper is a new type of dampers, whose structure including magnetic fluids, permanent magnet and a non-magnetic container. Inside the non-magnetic container, magnetic fluids supports the permanent magnet to suspense in it and moves as a working element. Under the influence of external oscillatory inertia forces, the movement of the permanent magnet leads the damper to a viscous dissipation of the oscillating system energy. This kind of viscous damper is very suitable for spacecraft under low frequency oscillation. In our experiments, model of magnetic fluids viscous damper and its test circuit were designed. The result of tests indicates that the damper based on magnetic fluids can suppress the low frequency oscillation.

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Wang, Guan Ming, Zhi Xue Lu, and Dan Huang. "Macro Program Design of Variational Trapezoid Curve Disk Cam." Advanced Materials Research 338 (September 2011): 689–96. http://dx.doi.org/10.4028/www.scientific.net/amr.338.689.

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Based on the design parameters of disc CAM with the oscillating roller follower and modified trapezoid curve follower motion, by introducing macro program cyclic variable, the mathematical calculation model of macro program about cutter path of disc CAM with the holonomic constraint oscillating roller follower is established. The macro program is designed to can be adjusted quickly, according to the design parameters and the process parameters. The numerical control program completely parametric design is realized. So it provides programming methods and strategies for numerical control machining macro program design of the oscillating roller follower disc CAM with a complicated movement law.

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Rieder, C. L., E. A. Davison, L. C. Jensen, L. Cassimeris, and E. D. Salmon. "Oscillatory movements of monooriented chromosomes and their position relative to the spindle pole result from the ejection properties of the aster and half-spindle." Journal of Cell Biology 103, no. 2 (August 1, 1986): 581–91. http://dx.doi.org/10.1083/jcb.103.2.581.

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During mitosis a monooriented chromosome oscillates toward and away from its associated spindle pole and may be positioned many micrometers from the pole at the time of anaphase. We tested the hypothesis of Pickett-Heaps et al. (Pickett-Heaps, J. D., D. H. Tippit, and K. R. Porter, 1982, Cell, 29:729-744) that this behavior is generated by the sister kinetochores of a chromosome interacting with, and moving in opposite direction along, the same set of polar microtubules. When the sister chromatids of a monooriented chromosome split at the onset of anaphase in newt lung cells, the proximal chromatid remains stationary or moves closer to the pole, with the kinetochore leading. During this time the distal chromatid moves a variable distance radially away from the pole, with one or both chromatid arms leading. Subsequent electron microscopy of these cells revealed that the kinetochore on the distal chromatid is free of microtubules. These results suggest that the distal kinetochore is not involved in the positioning of a monooriented chromosome relative to the spindle pole or in its oscillatory movements. To test this conclusion we used laser microsurgery to create monooriented chromosomes containing one kinetochore. Correlative light and electron microscopy revealed that chromosomes containing one kinetochore continue to undergo normal oscillations. Additional observations on normal and laser-irradiated monooriented chromosomes indicated that the chromosome does not change shape, and that the kinetochore region is not deformed, during movement away from the pole. Thus movement away from the pole during an oscillation does not appear to arise from a push generated by the single pole-facing kinetochore fiber, as postulated (Bajer, A. S., 1982, J. Cell Biol., 93:33-48). When the chromatid arms of a monooriented chromosome are cut free of the kinetochore, they are immediately ejected radially outward from the spindle pole at a constant velocity of 2 micron/min. This ejection velocity is similar to that of the outward movement of an oscillating chromosome. We conclude that the oscillations of a monooriented chromosome and its position relative to the spindle pole result from an imbalance between poleward pulling forces acting at the proximal kinetochore and an ejection force acting along the chromosome, which is generated within the aster and half-spindle.

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Henke, K. G., and C. E. Sullivan. "Effects of high-frequency oscillating pressures on upper airway muscles in humans." Journal of Applied Physiology 75, no. 2 (August 1, 1993): 856–62. http://dx.doi.org/10.1152/jappl.1993.75.2.856.

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We examined the effects of high-frequency- (30-Hz) low-pressure oscillations (< 1 cmH2O) applied to the upper airway, via a nose mask, on genioglossus (EMGgg), sternomastoid (EMGsm), and diaphragm electromyogram (EMGdia) activity in sleeping humans. Ten patients with sleep apnea and six normal subjects were studied. The pressure oscillations were applied through the mask for a single breath. The subjects were studied in non-rapid-eye-movement (NREM) and rapid-eye-movement (REM) sleep. In the normal subjects, during NREM sleep, peak EMGgg, EMGsm, and EMGdia activity increased significantly in response to the oscillations in 63, 51, and 46%, respectively, of all trials. During REM sleep, significant increases occurred in 73, 88, and 13%, respectively, of all trials. Similar responses were observed in the patients with obstructive sleep apnea. Peak EMGgg, EMGsm, and EMGdia activity increased significantly in 74, 50, and 67%, respectively, of all NREM sleep trials and in 55, 81, and 76%, respectively, of all REM sleep trials. An important finding was that in 46% of the trials in the patients with sleep apnea the oscillation-induced increase in EMGgg activity was associated with a partial or complete reversal of the upper airway obstruction with an increase in tidal volume. This was observed in NREM and REM sleep. We conclude that there are upper airway receptors that respond to low-pressure-high-frequency oscillations applied to the upper airway that have input to the genioglossus and other muscles of respiration. These responses may be utilized in future treatment for sleep apnea.

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Kobayashi, H. "Effects of Shock Waves on Aerodynamic Instability of Annular Cascade Oscillation in a Transonic Flow." Journal of Turbomachinery 111, no. 3 (July 1, 1989): 222–30. http://dx.doi.org/10.1115/1.3262259.

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The effects of shock waves on the aerodynamic instability of annular cascade oscillation were examined for rows of both turbine and compressor blades, using a controlled-oscillating annular cascade test facility and a method for accurately measuring time-variant pressures on blade surfaces. The nature of the effects and blade surface extent affected by shock waves were clarified over a wide range of Mach number, reduced frequency, and interblade phase angle. Significant unsteady aerodynamic forces were found generated by shock wave movement, which markedly affected the occurrence of compressor cascade flutter as well as turbine cascade flutter. For the turbine cascade, the interblade phase angle significantly controlled the effect of force, while for the compressor cascade the reduced frequency controlled it. The chordwise extent of blade surface affected by shock movement was estimated to be approximately 6 percent chord length.

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Bel’kov, V. M. "Damping of the track horizontal, transversal vibrations." Vestnik of the Railway Research Institute 78, no. 6 (January 4, 2020): 372–82. http://dx.doi.org/10.21780/2223-9731-2019-78-6-372-382.

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Knowledge of the oscillation process nature in horizontal plane across the track allows selecting the way of damping for reducing decrease of strength properties of polymer gaskets, rails, sleepers and earthworks under effect of horizontal vibrodynamic loads occurring during the rolling stock movement. Maximum horizontal deformation of polymer gaskets across the track does not exceed 10% therefore stress and deformation of polymer material can be done using the Hooke’s law.This is the first systematization of formulae for calculation of polymer gaskets, as well as the first resolution of the task when not pure shear takes place under effect of tangential stresses with simultaneous effect of vertical load. Damping coefficient of polyurethane gaskets is the same as for rubber gaskets; however, their service life is 2.5 times longer.Based on the presented physical mesomechanics it is demonstrated regarding the surface layer of two metal bodies contact under significant load that the surface mesolayer has damping properties, and vibrating oscillations occurring in the truck wheels when rolling stock moves on the rails will be reflected from the contact pad. The process of wheel and rail sliding in transversal direction is accompanied with increase of the total rolling friction and noise, elevated wear and tear of rails and wheel rims. In order to reduce transversal deformations and amplitude of the rails and sleepers torsion oscillations during rolling movement it is proposed to change the shape of polyurethane gaskets. Gaskets with variable thickness will more effectively reflect the shear transversal oscillating waves and reduce transversal forces.

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Anstis, Stuart M., and Brian J. Rogers. "Illusory Continuous Motion from Oscillating Positive-Negative Patterns: Implications for Motion Perception." Perception 15, no. 5 (October 1986): 627–40. http://dx.doi.org/10.1068/p150627.

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A black and white (positive) grating pattern was superimposed in exact register on its own photographic negative. Four operations were repetitively applied to this positive pattern so that it moved fractionally to the right, grew dimmer, moved back to the left, and grew brighter again. This sequence produced a strong illusion of continuous apparent motion to the right for as long as the cycle was repeated. The small relative motion between the two patterns generated two new illusory effects: enhanced real movement (ERM) and reversed real movement (RRM). The dimming and brightening phases gave rise to reversed apparent movement (RAM). All three effects are attributed to spatial filtering by neural mechanisms, which shifts the effective position of the positive-negative contours.

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Ruhland, Johannes, and Christian Breitsamter. "Numerical analysis of high-lift configurations with oscillating flaps." CEAS Aeronautical Journal 12, no. 2 (April 2021): 345–59. http://dx.doi.org/10.1007/s13272-021-00498-7.

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AbstractThis study presents two-dimensional aerodynamic investigations of various high-lift configuration settings concerning the deflection angles of droop nose, spoiler and flap in the context of enhancing the high-lift performance by dynamic flap movement. The investigations highlight the impact of a periodically oscillating trailing edge flap on lift, drag and flow separation of the high-lift configuration by numerical simulations. The computations are conducted with regard to the variation of the parameters reduced frequency and the position of the rotational axis. The numerical flow simulations are conducted on a block-structured grid using Reynolds Averaged Navier Stokes simulations employing the shear stress transport $$k-\omega $$ k - ω turbulence model. The feature Dynamic Mesh Motion implements the motion of the oscillating flap. Regarding low-speed wind tunnel testing for a Reynolds number of $$0.5 \times 10^{6}$$ 0.5 × 10 6 the flap movement around a dropped hinge point, which is located outside the flap, offers benefits with regard to additional lift and delayed flow separation at the flap compared to a flap movement around a hinge point, which is located at 15 % of the flap chord length. Flow separation can be suppressed beyond the maximum static flap deflection angle. By means of an oscillating flap around the dropped hinge point, it is possible to reattach a separated flow at the flap and to keep it attached further on. For a Reynolds number of $$20 \times 10^6$$ 20 × 10 6 , reflecting full scale flight conditions, additional lift is generated for both rotational axis positions.

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Yang, Xian Hai, and Hai Xing Zhao. "Optimum Design of Movement Parameters for Soft Plastic Vibration Sorting Machine’s Screen." Advanced Materials Research 383-390 (November 2011): 2875–79. http://dx.doi.org/10.4028/www.scientific.net/amr.383-390.2875.

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According to the circumstance of soft plastic oscillating separator’s movement, a mechanical model of the mutual movement for material and screen is established, and reached the relative motion equation. Through building the mathematical model to optimize the parameter of the materials of different density that on the same vibrating screen, we can get the optimal parameter for the successful separation.

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Heed, Tobias, and Brigitte Roeder. "Spatial codes for movement coordination do not depend on developmental vision." Seeing and Perceiving 25 (2012): 51. http://dx.doi.org/10.1163/187847612x646721.

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When people make oscillating right–left movements with their two index fingers while holding their hands palms down, they find it easier to move the fingers symmetrically (i.e., both fingers towards the middle, then both fingers to the outside) than parallel (i.e., both fingers towards the left, then both fingers towards the right). It was originally proposed that this effect is due to concurrent activation of homologous muscles in the two hands. However, symmetric movements are also easier when one of the hands is turned palm up, thus requiring concurrent use of opposing rather than homologous muscles. This was interpreted to indicate that movement coordination relies on perceptual rather than muscle-based information (Mechsner et al., 2001). The current experiment tested whether the spatial code used in this task depends on vision. Participants made either symmetrical or parallel right–left movements with their two index fingers while their palms were either both facing down, both facing up, or one facing up and one down. Neither in sighted nor in congenitally blind participants did movement execution depend on hand posture. Rather, both groups were always more efficient when making symmetrical rather than parallel movements with respect to external space. We conclude that the spatial code used for movement coordination does not crucially depend on vision. Furthermore, whereas congenitally blind people predominately use body-based (somatotopic) spatial coding in perceptual tasks (Röder et al., 2007), they use external spatial codes in movement tasks, with performance indistinguishable from the sighted.

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Kahr, Matthias, Michael Stifter, Harald Steiner, Wilfried Hortschitz, Gabor Kovacs, Andreas Kainz, Johannes Schalko, and Franz Keplinger. "MOEMS Based Single Chip Lorentz Force Magnetic Gradiometer." Proceedings 2, no. 13 (December 21, 2018): 724. http://dx.doi.org/10.3390/proceedings2130724.

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The functional principle of an optical gradient magnetic field sensor consisting of two independent laterally oscillating masses on a single chip is reported. These oscillations are caused by the Lorentz forces resulting from an alternating current through the masses interacting with a static magnetic field. Light is modulated by relative in-plane movement of the masses and a fixed frame and subsequently detected by two photodiodes. Evaluation of magnitude and phase of the output signal reveals information about the uniformity of the magnetic field. The sensor is capable of detecting uniaxially strength and direction of magnetic gradient fields, offset gradient fields and homogeneous fields.

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Nasibullayev, I. Sh, and E. Sh Nasibullaeva. "Influence of various types of frictional force on the movement of the piston in the pipe." Proceedings of the Mavlyutov Institute of Mechanics 8, no. 1 (2011): 257–65. http://dx.doi.org/10.21662/uim2011.1.025.

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The influence of viscous and dry friction on the movement of the piston inside the cylinder under the effect of an oscillating pressure gradient is considered. Equations of piston and fluid motion are solved numerically.

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Dzergach, A. I. "Laser Accelerators with Onward or Oscillating Movement of Plasmoids in Radio-Wells." Europhysics Letters (EPL) 21, no. 8 (March 10, 1993): 821–24. http://dx.doi.org/10.1209/0295-5075/21/8/005.

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Nasibullayev, I. Sh, and E. Sh Nasibullaeva. "The movement of the piston in a cylindrical tube with viscous friction." Proceedings of the Mavlyutov Institute of Mechanics 9, no. 2 (2012): 107–12. http://dx.doi.org/10.21662/uim2012.2.059.

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The paper considers the numerical simulation of piston motion with a spring in a cylindrical tube under the influence of an oscillating pressure difference with taking into account the action of dry and viscous friction. The time is determined for establishing the periodic mode of motion of the piston and the nature of its motion, depending on the various types of friction and spring stiffness.

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Fultz, Nina E., Giorgio Bonmassar, Kawin Setsompop, Robert A. Stickgold, Bruce R. Rosen, Jonathan R. Polimeni, and Laura D. Lewis. "Coupled electrophysiological, hemodynamic, and cerebrospinal fluid oscillations in human sleep." Science 366, no. 6465 (October 31, 2019): 628–31. http://dx.doi.org/10.1126/science.aax5440.

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Sleep is essential for both cognition and maintenance of healthy brain function. Slow waves in neural activity contribute to memory consolidation, whereas cerebrospinal fluid (CSF) clears metabolic waste products from the brain. Whether these two processes are related is not known. We used accelerated neuroimaging to measure physiological and neural dynamics in the human brain. We discovered a coherent pattern of oscillating electrophysiological, hemodynamic, and CSF dynamics that appears during non–rapid eye movement sleep. Neural slow waves are followed by hemodynamic oscillations, which in turn are coupled to CSF flow. These results demonstrate that the sleeping brain exhibits waves of CSF flow on a macroscopic scale, and these CSF dynamics are interlinked with neural and hemodynamic rhythms.

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Deineka, Kateryna, and Yurii Naumenko. "ESTABLISHING THE ROTATION SPEED VARIATION RANGE LIMITS FOR AUTO-EXCITATION OF SELF-OSCILLATING GRINDING IN A TUMBLING MILL." Technology transfer: fundamental principles and innovative technical solutions 4 (November 30, 2020): 32–35. http://dx.doi.org/10.21303/2585-6847.2020.001479.

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The influence of the structure of a two-fraction polygranular feed of the chamber on the value of the drum rotation speed at auto-excitation of self-excited oscillations with a maximum swing is considered. Such a pulsating mode of movement of the charge is used in the self-oscillating process of grinding in a tumbling mill. The coarse fraction simulated the grinding bodies was steel bullets with a relative size ψdb=0.026. The fine fraction, simulated the particles of the crushed material, was a cement clinker with a relative particle size ψdm=0.00013. Variable factors of experimental studies were: the degree of filling the chamber in the state of rest κbr=0.25; 0.29; 0.33 and the degree of filling the gaps between the particles of the coarse fraction with particles of the fine fraction κmbgr=0.0625; 0.375; 0.6875; 1. The method of visual analysis of transient processes of self-oscillating modes of feed behavior in the cross section of the rotating drum chamber is applied. Measurements of the speed limits of the drum rotation were carried out with auto-excitation of self-oscillations of the filling. The magnitude of the self-oscillation swing was estimated by the increase in the difference between the maximum and minimum values of the filling dilatancy for one period of pulsations. An increase in the upper limit of the speed range ψω2 with a decrease in κbr and κmbgr was established. The growth rate of ψω2 increases at low values of κbr and κmbgr. Some increase in the lower limit of the ψω1 range with a decrease in κbr and κmbgr was revealed. An increase in the range of speeds of rotation was recorded at the maximum range of self-oscillations ψω1–ψω2 with a decrease in the connected interaction of the intra-mill filling. This coherent interaction is due to an increase in κbr and κmbgr. The value of the ψω1–ψω2 range varies from 1.01–1.03 at κbr=0.33 and κmbg=1 to 1.22–1.66 at κbr=0.25 and κmbgr=0.0625. The range gets its maximum value with fine and superfine grinding

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Sengupta, Arijit, Anh Vu, Xianghong Qian, and S. Ranil Wickramasinghe. "Remote Performance Modulation of Ultrafiltration Membranes by Magnetically and Thermally Responsive Polymer Chains." Membranes 11, no. 5 (May 4, 2021): 340. http://dx.doi.org/10.3390/membranes11050340.

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Ultrafiltration membranes, that respond to an external magnetic field and local temperature have been developed. Surface-initiated activator-generated electron transfer (AGET) atom transfer radical polymerization (ATRP) has been used to graft poly(N-isopropylacrylamide) (PNIPAm) from the surface of 300 kDa regenerated cellulose membranes. The polymerization initiator was selectively attached to the entire membrane surface, only the outer membrane surface or only the inner pore surface. A superparamagnetic nanoparticle was attached to the end of the polymer chain. The DI water flux as well as the flux and rejection of bovine serum albumin were investigated in the absence and presence of a 20 and 1000 Hz oscillating magnetic field. In an oscillating magnetic field, the tethered superparamagnetic nanoparticles can cause movement of the PNIPAm chains or induce heating. A 20 Hz magnetic field maximizes movement of the chains. A 1000 Hz magnetic field leads to greater induced heating. PNIPAm displays a lower critical solution temperature at 32 °C. Heating leads to collapse of the PNIPAm chains above their Lower Critical Solution Temperature (LCST). This work highlights the versatility of selectively grafting polymer chains containing a superparamagnetic nanoparticle from specific membrane locations. Depending on the frequency of the oscillating external magnetic field, membrane properties may be tuned.

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Meng, Zhao Ming, Ya Bo Qiao, and Zhi Min Fan. "The Optimal Design of Oscillating Oil Cylinder Mechanism of Tire Building Machine." Advanced Materials Research 87-88 (December 2009): 206–10. http://dx.doi.org/10.4028/www.scientific.net/amr.87-88.206.

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according to the poor quality situation that tire building machine presses tire in current market, the thesis analyses the reasons that press roll presses tire uncompactedly and tire layer has bubbles in the process of tire building machine repression. A new design method that is the optimal design of oscillating oil cylinder mechanism of tire building machine is presented. In the premise of meeting the movement performance of mechanism, it not only can maintain that the pressing roll fits in the best pressure, but also enables wave motion of fitting tire pressure in the allowable scope when mechanism is in the dynamic movement. The article cites examples of the design, demonstrates the superiority of the new design method fully.

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Zhang, Li Zhen, and Wei Wei Li. "The Design of Oscillating Hydrofoil Current Generation Device." Applied Mechanics and Materials 733 (February 2015): 535–38. http://dx.doi.org/10.4028/www.scientific.net/amm.733.535.

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The oscillating hydrofoil current generation device utilizes a typical movement type, which can transform energy effectively from current. The study shows that the geometrical profile of blades is the fundamental factor to the efficiency. In order to resolve the problem, this paper adapt the BEM(blade elements momentum) theory, which plays an important role in resolving the turbine blade design. Use the MATLAB to calculate of the constraint equations, then translate the coordinates which has got through the calculation to Solidworks which is a convenient 3D modeling soft. In the end we will give an example which has modeled 3-D hydrofoil BEM theory.

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Mandelkow, E. M., E. Mandelkow, and R. A. Milligan. "Microtubule dynamics and microtubule caps: a time-resolved cryo-electron microscopy study." Journal of Cell Biology 114, no. 5 (September 1, 1991): 977–91. http://dx.doi.org/10.1083/jcb.114.5.977.

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Microtubules display the unique property of dynamic instability characterized by phase changes between growth and shrinkage, even in constant environmental conditions. The phases can be synchronized, leading to bulk oscillations of microtubules. To study the structural basis of dynamic instability we have examined growing, shrinking, and oscillating microtubules by time-resolved cryo-EM. In particular we have addressed three questions which are currently a matter of debate: (a) What is the relationship between microtubules, tubulin subunits, and tubulin oligomers in microtubule dynamics?; (b) How do microtubules shrink? By release of subunits or via oligomers?; and (c) Is there a conformational change at microtubule ends during the transitions from growth to shrinkage and vice versa? The results show that (a) oscillating microtubules coexist with a substantial fraction of oligomers, even at a maximum of microtubule assembly; (b) microtubules disassemble primarily into oligomers; and (c) the ends of growing microtubules have straight protofilaments, shrinking microtubules have protofilaments coiled inside out. This is interpreted as a transition from a tense to a relaxed conformation which could be used to perform work, as suggested by some models of poleward chromosome movement during anaphase.

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Apushkinskaya, D., E. Apushkinskiy, and M. Astrov. "Movement of a vortex filament near oscillating pinning centers in the hard superconductor." Journal of Physics: Conference Series 633 (September 21, 2015): 012114. http://dx.doi.org/10.1088/1742-6596/633/1/012114.

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Wang, Yinghao, Jianfeng Wu, Hongchun Yang, Zhichuan Tang, and Guozhong Chai. "Evaluation of a New Rotator Cuff Trainer Based on Oscillating Hydraulic Damping." Healthcare 8, no. 1 (January 28, 2020): 24. http://dx.doi.org/10.3390/healthcare8010024.

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In order to provide a convenient way to strengthen the rotator cuff muscles and prevent rotator cuff injury, this study designed an innovative strength trainer specifically for shoulder rotator cuff based on oscillating hydraulic damping. We carried out a myoelectric testing experiment to evaluate the shoulder rotation training effect and compared the results with traditional training equipment to verify the feasibility and validity of the new rotator cuff trainer (RCT). Then, we further explored the influence of different training postures and motion speeds on shoulder rotation training. In the experiment, subjects used three types of equipment (RCT, dumbbells and elastic bands) to perform shoulder rotation training under two movement speeds and two motion postures. The surface electromyography (sEMG) signals of targeted muscles were collected in real time and then further analyzed. The experimental results showed that when using the RCT, the muscle force generation sequence was more aligned with the biomechanical principles of shoulder rotation than using the other two training methods, and the target training muscles had the higher percentage of muscle work. During RCT training, a higher speed of movement (120°/s) led to a higher degree of muscle activation; coronal axis rotation was better for the infraspinatus training, and sagittal axis rotation was better for teres minor training. Based on these results, the RCT was proved to be more effective than traditional training methods. In order to exercise the different muscles of rotator cuff more comprehensively and extensively, different postures should be selected. Furthermore, the movement speed can be appropriately increased within the safe range to improve muscle activation.

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Sharaby, Noureldin N., Artyom A. Doroshenko, and Andrey V. Butovchenko. "Simulation of Sesame Seeds Outflow in Oscillating Seed Metering Device Using DEM." Engineering Technologies and Systems 30, no. 2 (June 30, 2020): 219–31. http://dx.doi.org/10.15507/2658-4123.030.202002.219-231.

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Introduction. Sesame crop is one of the most important export crops in many countries around the world, especially in Africa. To meet the agricultural requirement of precision planting, various types of precision seed planters have been developed. Numerous studies were carried out to study the optimisation of the parameters of the precision planting. One of these parameters, affecting the quality of the precision seeder, is the grain outflow from the seed metering device. Materials and Methods. In order to maintain good continuous performance of an oscillating seeder, it is important to monitor seed flow in real-time and adjust oscillation parameters automatically. Existing research methods, such as prototyping and monitoring the process using a high-speed camera, by reason of the random movement of particles, do not allow obtaining sufficient data to understand trajectories and velocities of particles and existing equations for particle motion when simulating the sowing process do not allow taking into account the interaction of particles that having various shapes, rolling and sliding friction coefficients, and the elastic modulus of particle materials and a working body. In this study, the outflow rate of sesame seeds in an oscillating seed metering device was modeled using the simulation method based on the discrete element method. The aim of this study is to create a simulation model of an oscillating-type sowing planter using the sowing sesame seeds as an example for evaluating the effectiveness of this model, and the possibility of further optimization and prediction of sowing seeds with this device. Results. The analysis of the results showed that during the simulation, the sowing rate of sesame seeds when leaving the oscillating seed metering holes has significant differences in number and direction. The results of the modeling process in this study showed that when opening a hole in the oscillating seeder, a number of sesame seeds from 0 to 4 were coming out of it. The resulting model allows monitoring the behavior of each particle of a sesame seed, analyzing its trajectory, speed, and forces acting on it at any one time, and varying the parameters to obtain the dependence of uneven seeding on the kinematic and geometric parameters of the device. Discussion and Conclusion. The obtained simulation results provide an effective method for predicting the consumption of sesame seeds from the oscillating seed meter, which serves as the basis for optimizing the kinematic and geometric parameters of the oscillating sowing device in order to increase its efficiency. This model is universal and can be adapted to sow other crops.

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Su, Yu Min, Shi Qi Zhao, and Liang Yang. "Experimental Study and Hydrodynamic Performance Analysis of a Bio-Tail Fin Propellant System." Key Engineering Materials 419-420 (October 2009): 77–80. http://dx.doi.org/10.4028/www.scientific.net/kem.419-420.77.

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In order to research the bionic mechanics in unsteady flow and the hydrodynamic performance of the oscillating tail fin, in this paper, an experimental device imitating bionic tail fin were built, the design concepts and the rolling systems of the mechanical tail fins were demonstrated, including the procedures and correlated works on the selection of the servo motors, online control and signal data collecting and processing. The movements of the mechanical tail fin could be optimized by the comparisons of the propulsion efficiency, thrust coefficient, lateral force coefficient and torque coefficient at different conditions. Meanwhile, error analysis is carried out to correct the movement curves and obtain more precise experimental data and results.

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Ma, Hongwei, Yueri Cai, Yuliang Wang, Shusheng Bi, and Zhao Gong. "A biomimetic cownose ray robot fish with oscillating and chordwise twisting flexible pectoral fins." Industrial Robot: An International Journal 42, no. 3 (May 18, 2015): 214–21. http://dx.doi.org/10.1108/ir-11-2014-0426.

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Purpose The paper aims to develop a cownose ray-inspired robotic fish which can be propelled by oscillating and chordwise twisting pectoral fins. Design/methodology/approach The bionic pectoral fin which can simultaneously realize the combination of oscillating motion and chordwise twisting motion is designed based on analyzing the movement of cownose ray’s pectoral fins. The structural design and control system construction of the robotic fish are presented. Finally, a series of swimming experiments are carried out to verify the effectiveness of the design for the bionic pectoral fin. Findings The experimental results show that the deformation of the bionic pectoral fin can be well close to that of the cownose ray’s. The bionic pectoral fin can produce effective angle of attack, and the thrust generated can propel robotic fish effectively. Furthermore, the tests of swimming performance in the water tank show that the robotic fish can achieve a maximum forward speed of 0.43 m/s (0.94 times of body length per second) and an excellent turning maneuverability with a small radius. Originality/value The oscillating and pitching motion can be obtained simultaneously by the active control of chordwise twisting motion of the bionic pectoral fin, which can better imitate the movement of cownose ray’s pectoral fin. The designed bionic pectoral fin can provide an experimental platform for further study of the effect of the spanwise and chordwise flexibility on propulsion performance.

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Chomczyk, W., W. Ostapski, J. Piotrowski, and T. Tataj. "Oilless and frictionless compressor with double-sided rotationally oscillating piston." Bulletin of the Polish Academy of Sciences: Technical Sciences 61, no. 2 (June 1, 2013): 485–98. http://dx.doi.org/10.2478/bpasts-2013-0048.

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Abstract The contents are concerned with a concept of an oilless and frictionless compressor operating without dead movement and having functional parameters superior to compressors of renowned manufacturers. The concept is based on patents No. 68220, 83060, P377851 by W. Chomczyk and patents P394072, P385733 by W. Chomczyk, W. Ostapski and J. Piotrowski. The proposed design of an oilless compressor ensures volumetric efficiency higher than that encountered in conventional compressors. It also generates pure compressed medium without necessity of filtering from oil particles, which is especially desired in food, pharmaceutical, medical, fragrance, chemical and automation industry.

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Derevich, Igor, and Olga Soldatenko. "Movement and Heat Transfer of Particles in Inhomogeneous and Nonisothermal Rapidly Oscillating Fluid Flow." Journal of Applied Mathematics and Physics 02, no. 07 (2014): 708–17. http://dx.doi.org/10.4236/jamp.2014.27078.

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Mills, Richard S., and Heidi Sveistrup. "Kinematics and postural muscular activity during continuous oscillating platform movement in children and adolescents." Experimental Brain Research 236, no. 5 (March 17, 2018): 1479–90. http://dx.doi.org/10.1007/s00221-018-5228-0.

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Journal articles on the topic 'Oscillating movement'

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